AIM:· To investigate the useof Cepstral measures like Cepstral Peak Prominence (CPP) and smoothenedCepstral Peak Prominence (sCPP) to assess dysphonia severity in individualswith Gastroesophageal reflux disease (GERD).Subjects:Thestudy included 2 groups. The first group with consisted of 20 patients,consisting of 11 males and 9 females aged between 20 to 60 years diagnosed withGastroesophageal reflux disease (GERD) whose voice sample were selected fromthe CSL4500 (KayPentax) database.
The second group consisted of normal age andgender matched individuals. Subject selection criteria:Inclusion criteria:· Those with a clinicaldiagnosis of Gastroesophageal reflux disease (GERD) on stroboscopic examination· Those who did not havehearing loss, hormonal problems, respiratory illness, psychological problems,neurological problems, smoking and alcohol consumption.Exclusion Criteria:· Those who reported ofchronic smoking.· Those who reposted ofhave hearing loss, hormonal problems, respiratory illness, psychologicalproblems, neurological problems.Test environment:Therecordings were carried out in a sound treated lab following ANSI S12.2-2008 standards.
Equipment used: · Multi-Dimensional VoiceProfile (MDVP) modules of computerized Speech Lab (CSL) software; Model 4500(KayPentax)· A Shure mic belongingto CSL4500· Speech tool program Version 1.65 by James Hillenbrand· Stroboscope Direct Rigid Laryngoscope (Xion Endostrob DX) was used tovisualize the vocal folds Procedure:General Assessment: Detailed case history which included onset of problem,duration of symptoms, associated voice problems and medical management wastaken for individuals with GERD. Additional information regarding theindividual’s lifestyle like smoking or drinking habits, daily use of voice,diet, history of hearing loss, hormonal problems, respiratory illness,psychological problems, neurological problems was also noted for both groupsInstructions and recording: All recordingshad been made in a sound-treated lab on CSL4500 using a Shure microphone belongingto CSL, KayPentax.
All participants had been instructed to vocalize a sustainedvowel /a/ for more than 8 seconds with a voice reflecting their usual pitch,strength, and quality in a sitting position. All the files were saved as .wavefiles on the CSL4500 system. These files were then transferred to a laptop (DELL,Inspiron 15) for analyses using the Speech tool program Version 1.65Data Analysis:Phonationsamples recorded from both these groups was edited to retain the middle andstable portion of vowel /a/ for duration of 3 sec. Sustained vowel samples wereanalyzed by measuring CPP and sCPP, using the algorithm and computer softwareprogram (Speech tool program Version 1.65)for calculating sCPP obtained from Hillenbrand.
The computer algorithm thencalculated CPP and sCPP for each sample. The CPP, in CSL was calculated bysubtracting the value of the peak from the apparent baseline signal.